Alpine authorities have registered a significant increase in the number of human remains discovered last month, with the body of a man missing for 30 years the most recent to be uncovered.

Rescue teams in Saas Valley in the Valais canton were called last Tuesday after two climbers retreating from an aborted ascent spotted a hand and two shoes protruding from the Hohlaub glacier.

Rescuers spent two hours freeing the mummified body with icepicks and their bare hands, also recovering a silver wristwatch and a ring. A helicopter flew the remains to Bern, where forensics experts matched the DNA to that of a German citizen, born in 1943, who had gone missing on a hike in 11 August 1987.

One rescue worker said the man had worn shoes “unsuitable” for walking on ice, suggesting he may have slipped after walking a few metres onto the glacier and fallen down a crevice. Both feet had become detached from the body, indicating the force of the fall.

The discovery comes less than a week after the bodies of a Swiss couple, missing for 75 years, were found in the Tsanfleuron glacier in the same canton. Marcelin and Francine Dumoulin had disappeared after going out to milk their cows in a meadow above Chandolin on 15 August 1942.

A bottle found near the remains of a couple found preserved in a receding glacier, near Les Diablerets, Switzerland. Photograph: AFP/Getty Images

Last Thursday, the remains of a person believed to have been killed in an Air India crash more than 50 years ago was also discovered in the French Alps, on Mount Blanc.

Switzerland’s glaciers have been melting at an unprecedented rate, losing almost one cubic km in ice volume or about 900 bn litres of water over the past year. According to an investigation by Tagesanzeiger newspaper, eight of the 10 months in which the glaciers have lost the most in volume over the past century have been since 2008.

Since 1850, when glaciers covered 1,735 sq km (670 sq miles) of Swiss land, the total area has shrunk by a half, to about 890 sq km.

Police in Valais expect the bodies of many more missing persons to emerge because of global warming. “It’s quite clear,” a spokesman, Christian Zuber, told the Guardian.

“The glaciers are retreating, so it’s logical that we’re finding more and more bodies and body parts. In the coming years we expect that many more cases of missing persons will be resolved.”

He said a map that lists everyone who had gone missing since 1925 to the present day contains 306 names and locations, one fewer since the discovery of the German mountaineer.

At least 160 alpinists remain missing in France’s Mont Blanc massif, and the Morteratsch glacier in Graubünden is believed to contain the bodies of 40 mountaineers.

Police investigate the site where the body of a German hiker was found in the Valais canton near Saas-Fee, Switzerland. Photograph: AP

Zuber described the “great relief” at being able to pass on the information to the families “who would otherwise never know with 100% certainty whether their loved one had perished on the mountain. Finally when a corpse is discovered, you have an absolute guarantee”, he said.

He said that feeling had also been palpable earlier this year when a local woman was able to retrieve the bodies of her dead parents, the Dumoulins, who had disappeared when she was just four years old. “We locals are obviously used to the mountains, but such discoveries are no less emotional for the people here,” he said.

Rolf Trachsel, head of mountain rescue in Saas-Fee, who led the operation to recover the German man’s body, said it had been discovered in an area popular with hikers. “There was very little snow, and it was not very steep. It was about half an hour’s hike away from the next mountain cable-car station.”

He said although the team had to deal with the sad fact they were recovering a dead man, they also felt considerable relief. “If someone has gone missing, logic tells you their body has to turn up again one day,” Trachsel said.

“It’s obviously good that we can put our efforts into recovering someone, especially after 30 years, and knowing how important it is for the family to find out what happened.”

The body was taken to the Institute of Forensic Medicine (IRM) at the University of Bern by helicopter for examination and formal identification where it is still being held. Christian Jackowski, a scientist at IRM, said the discovery of human remains was now a regular feature of the Swiss summer holiday season, as climbers started to swarm the Valais region’s ice-covered mountains.

Usually bodies emerged from the ice at the top of the glacier, rather than its “tongue” at the bottom of the valley, Jackowski said. The extent to which bodies have been preserved by the ice depends on the circumstances of the person’s demise, with some human remains having been mummified by sunshine and dry winds before being engulfed in ice, while others have been reduced to skeletons.

The majority of bodies are trapped in ice, crevices or streams after an accident or a suicide, though some cases are treated in relation to criminal cases.

In most cases, forensic experts face a race against time once bodies have been removed from the ice and start to thaw. Dental records and DNA samples are checked against a database of missing people to determine the identity of the corpse.

Since 2000, authorities in Switzerland have taken DNA samples of missing people’s family members immediately after their disappearance to facilitate the process.